1. Field of the Invention
The present invention relates to a receiver capable of searching for receivable channels from a predetermined frequency band.
2. Description of the Related Art
Accompanying digitalization of communication and broadcasting and advancement in data compression technology, it is becoming possible to manage numerous channels as compared to analog communication and broadcasting. Particularly, as receivers receiving a digital broadcast, receivers capable of receiving in plural systems such as terrestrial digital broadcasting, cable digital broadcasting, satellite digital broadcasting, and the like are becoming popular.
A receiver capable of receiving in plural systems, particularly a receiver that receives a broadcast has a very wide effective frequency band as a receiving object, and thus requires a function to set channels by searching for channels to be used from this frequency band. In digital broadcasting for example, as measures to search for channels, there are known a full scan to scan the entire effective frequency band and a quick scan to scan a partial band with priority out of the effective frequency band to increase the scan speed (see, for example, JP-A 2005-303526 (KOKAI)).
However, to scan the entire effective frequency band, the frequency band used for broadcasting can be as wide as several hundred MHz, and thus a long period of time is needed until channel setting is completed and the user is able to view the channels. On the other hand, when performing the quick scan of a partial band with priority out of the frequency band, a non-scanned frequency may exist depending on the rule of prioritizing. Thus it is possible that all of the available channels cannot be covered.